1. Field of the Invention
The present invention relates to method and device for controlling motors in an automotive powered seat which permits adjustment in positions of seating adjusting mechanisms under a motor drive control for providing optimal seating positions for an occupant on the seat according to his or her taste and physique.
2. Description of Prior Art
A well know type of automotive powered seat is equipped with various seating posture adjusting mechanisms, such as a seat slide device, reclining device, and seat back bending device, with a view to enabling an occupant on the seat to adjust the seat in fore-and-aft direction and the inclination angle (reclining angle) of seat back.
This powered seat is used mainly in a driver's seat, but by contrast, an assistant's seat next to the drivers seat is manually operable for those seating posture adjustments.
In fact, an occupant on the assistant's seat usually wishes to select a normal seating posture for getting a good forward view field and sometimes to take an enjoy seating posture for sight-seeing through the window, or to take a relax seating posture for a rest or nap on that seat. Therefore, in the case of such assistant's seat, demand has been increased for an easy, quick adjustment in various seating postures, the same as in the foregoing driver's powered seat.
In constructing the assistant's seat in such a powered seat, an incentive arises to make more simple the switching operations in view of the inevitable troublesome switching works on plural switches for various intended seating postures.
A proposal in this respect would be to design the seat so that, for the relax seat position, the seat back may be greatly inclined backwardly, while the upper part of seat back is being bent or inclined forwardly.
However, when the occupant wants to descend from the seat in such relax position, he or she has to return the respective positions of seat back and its upper part to the normal position through the forward inclination motion of seat back on the whole and then through the backward tilt of the seat back upper part, in which case as well, the occupant encounters the troublesome switching operations for effecting those actions, and therefore it is hard for him or her to descend from the seat. Reversely, when the occupant wants to climb onto the seat which is set in the relax position, he or she has to do similar troublesome switching operations for placing the seat in the normal position in order to take a normal seating posture on the seat. This presents a difficulty to quick seating in this kind of powered seat.